The present invention relates to a bag for containing a liquid or powdery detergent or the like.
Conventionally, liquid or powdery detergents for household use and the like are packed in plastic containers for sale. When the detergent in the container is used up, for example, a user may purchase a detergent refill packed in a plastic bag and refill the empty container with the detergent refill.
The user performs a refilling operation to pour the detergent refill into the empty container by holding the flexible plastic bag in hand. However, the plastic bag is so flexible that the mouth of the bag is positionally unstable, making it difficult to perform the refilling operation with the container and the bag brought into mouth-to-mouth contact with each other. Therefore, the user is likely to inadvertently spill the detergent out of the container.
One known approach to this problem is that a plastic bag containing a detergent refill is set in an empty container on the top of which is provided a liquid dispenser having a pump with a nozzle and a suction tube projecting downward from the pump and, with the bag being pierced with the tube, the detergent is delivered out of the bag through the nozzle by operating up and down the pump.
In this case, not only a portion of the bag to be pierced with the tube but the entire bag is formed of a laminated film comprising a stretched nylon film and a polyolefin film. The stretched nylon film is liable to be torn by a force exerted thereon when the bag is pierced with the tube. The polyolefin film laminated with the stretched nylon film is also torn along with the stretched nylon film by the piercing force when the bag is pierced with the tip of the tube. Thus, the laminated film is torn, so that air flows into the bag through tears developed in the laminated film around a hole through which the tube penetrates. When the detergent in the bag is reduced to a small quantity, the air is sucked out through the tube by the operation of the pump, thereby making it impossible to completely deliver the detergent out of the bag. Further, when the container falls down, the detergent may leak out of the bag through the tears within the container to make the inside of the container dirty, or leak out of the container.
To solve the aforesaid problems, it is an object of the present invention to provide a bag which is free from development of tears around a hole formed therein when pierced with tubular or hollow needle suction means.
In accordance with a first aspect of the present invention to achieve the aforesaid object, there is provided a bag for containing a liquid or powdery material, the bag comprising a penetrable portion to be pierced with tubular or hollow needle suction means for delivering the material out of the bag, the penetrable portion comprising a laminated sheet having an outer layer including at least one of a calendered film (e.g., aluminum foil) and a stretched film, and an inner layer of an unstretched film, wherein a peeling strength between the outer layer and the inner layer is 0.0490 to 3.4323 N/15 mm width.
The bag according to the first inventive aspect is preferably of a so-called stand-pack type (self-supporting type) having an outwardly bulged bottom portion and a body portion, the bottom portion serving as the penetrable portion to be pierced with the suction means, the body portion comprising a laminated sheet having an inner layer of an unstretched film, the unstretched film of the inner layer of the body portion and the unstretched film of the inner layer of the bottom portion being fusion-bonded along a seam between the body portion and the bottom portion by heat sealing.
In accordance with a second aspect of the present invention, there is provided a bag for containing a liquid or powdery material, the bag comprising a penetrable portion to be pierced with tubular or hollow needle suction means for delivering the material out of the bag, the penetrable portion comprising a laminated sheet having an outer layer including at least one of a calendered film (e.g., aluminum foil) and a stretched film, an intermediate layer of an unstretched film, and an inner layer of an unstretched film, wherein a peeling strength between the outer layer and the intermediate layer is 0.0490 to 3.4323 N/15 mm width, and a peeling strength between the intermediate layer and the inner layer is 0.0490 to 3.4323 N/15 mm width.
The bag according to the second inventive aspect is preferably of a so-called stand-pack type (self-supporting type) having an outwardly bulged bottom portion and a body portion, the bottom portion serving as the penetrable portion to be pierced with the suction means, the body portion comprising a laminated sheet having an inner layer of an unstretched film, the unstretched film of the inner layer of the body portion and the unstretched films of the intermediate and inner layers of the bottom portion being fusion-bonded along a seam between the body portion and the bottom portion by heat sealing.
In accordance with a third aspect of the present invention, there is provided a bag for containing a liquid or powdery material, the bag comprising a penetrable portion to be pierced with tubular or hollow needle suction means for delivering the material out of the bag, the penetrable portion comprising a laminated sheet having an outer layer of an unstretched film, an intermediate layer including at least one of a calendered film (e.g., aluminum foil) and a stretched film, and an inner layer of an unstretched film, wherein a peeling strength between the outer layer and the intermediate layer is 0.0490 to 3.4323 N/15 mm width, and a peeling strength between the intermediate layer and the inner layer is 0.0490 to 3.4323 N/15 mm width.
The bag according to the third inventive aspect is preferably of a so-called stand-pack type (self-supporting type) having an outwardly bulged bottom portion and a body portion, the bottom portion serving as the penetrable portion to be pierced with the suction means, the body portion comprising a laminated sheet having an inner layer of an unstretched film, the unstretched film of the inner layer of the body portion and the unstretched film of the inner layer of the bottom portion being fusion-bonded along a seam between the body portion and the bottom portion by heat sealing.
The bags according to the invention, for example, are each set within a container for use, and pierced with the suction means which extends from a liquid or powder dispenser of the container so that the liquid or powdery material can be delivered out of the bag through the suction means. In accordance with the first inventive aspect, the penetrable portion of the bag to be pierced with the suction means is formed of the laminated sheet having the outer layer including at least one of the calendered film (e.g., aluminum foil) and the stretched film and the inner layer of the unstretched film as described above. A preferred example of the stretched film for the outer layer is a stretched nylon film. since preventive measures is required against degradation of the material to be contained in the bag depending on the kind of the material, the calendered film, e.g., an aluminum foil is preferably employed which provides a barrier effect. An inner surface of the outer layer may be comprised of the unstretched film, e.g., an unstretched polyolefin film such as an unstretched polyethylene film. In this case, the unstretched film for the inner layer may also be an unstretched polyolefin film such as an unstretched polyethylene film, and the unstretched polyolefin film in the inner surface of the outer layer is opposed to the unstretched polyolefin film of the inner layer. When an edge portion of the unstretched polyolefin film of the inner layer of the bottom portion not intended to be pierced with the suction means is fusion-bonded to an edge portion of the polyolefin film of the inner layer of the body portion by heat sealing for joining the bottom portion and the body portion together, the edge portions of the unstretched polyolefin film in the inner surface of the outer layer and the unstretched polyolefin film of the inner layer of the bottom portion are also fusion-bonded together by the heat sealing.
Since the outer layer and the inner layer of the laminated sheet for the bottom portion of the bag are bonded to each other with a peeling strength of 0.0490 to 3.4323 N/15 mm width, the inner layer is easily separated from the outer layer when the laminated sheet is pierced with the suction means. The easy separation between the outer layer and the inner layer occurring when the laminated sheet is pierced with the suction means permits the inner layer to be disconnected from the outer layer thereby to prevent the inner layer from being torn even if at least one of the calendered film (aluminum foil) and the stretched film is torn by the piercing. Therefore, at least the inner layer is intimately fitted around the suction means which pierces into the bag, so that air is unlikely to flow into the bag. Even if the material contained in the bag is reduced to a small quantity, the material remaining in the bag can almost completely be delivered out of the bag.
According to the first inventive aspect, the peeling strength between the outer layer and the inner layer is 0.0490 to 3.4323 N/15 mm width as described above. If the peeling strength is lower than 0.0490 N/15 mm width, the outer layer and the inner layer of the laminated sheet are too easily separated from each other in handling the laminated sheet before the production of the bag, resulting in a poor operability. Where the inner surface of the outer layer is comprised of the unstretched film, however, delamination of the laminated sheet of the bottom portion along the seam between the bottom portion and the body portion of the finished bag is prevented even if the peeling strength is low. This is because the unstretched film in the inner surface of the outer layer and the unstretched film of the inner layer of the bottom portion are fusion-bonded to the unstretched film of the inner layer of the body portion along the seam by the heat sealing. Where the unstretched film is not provided in the inner surface of the outer layer, a peeling strength of greater than about 0.3432 N/15 mm width between the outer layer and the inner layer is required. If the peeling strength between the outer layer and the inner layer is higher than 3.4323 N/15 mm width, the inner layer is less liable to be separated from the outer layer when the bag is pierced with the suction means.
In accordance with the second inventive aspect, a preferred example of the stretched film for the outer layer is a stretched nylon film as in accordance with the first inventive aspect. Since preventive measures is required against degradation of the material to be contained in the bag depending on the kind of the material, a calendered film such as an aluminum foil is preferably employed which provides a barrier effect. An inner surface of the outer layer may be comprised of an unstretched film, e.g., an unstretched polyolefin film such as an unstretched polyethylene film. In this case, the unstretched film for the intermediate layer or the inner layer may also be an unstretched polyolefin film such as an unstretched polyethylene film, and the unstretched polyolefin film of the intermediate layer is opposed to the unstretched polyolefin film in the inner surface of the outer layer and to the unstretched polyolefin film of the inner layer. When an edge portion of the unstretched polyolefin film of the inner layer of the bottom portion not intended to be pierced with the suction means is fusion-bonded to an edge portion of the polyolefin film of the inner layer of the body portion by heat sealing for joining the bottom portion and the body portion together, the edge portions of the unstretched polyolefin film in the inner surface of the outer layer, the unstretched polyolefin film of the intermediate layer and the unstretched polyolefin film of the inner layer of the bottom portion are also fusion-bonded together by the heat sealing.
Where the unstretched film is not provided in the inner surface of the outer layer, the intermediate layer is comprised of a laminated film including an unstretched polyolefin film provided on an inner side thereof and another unstretched film such as an unstretched nylon film, and the unstretched polyolefin film of the intermediate layer is opposed to the unstretched polyolefin film of the inner layer. When an edge portion of the unstretched polyolefin film of the inner layer of the bottom portion not intended to be pierced with the suction means is fusion-bonded to an edge portion of the polyolefin film of the inner layer of the body portion by heat sealing for joining the bottom portion and the body portion together, the edge portions of the unstretched polyolefin film of the intermediate layer and the unstretched polyolefin film of the inner layer of the bottom portion are also fusion-bonded together by the heat sealing.
In the laminated sheet according to the second inventive aspect, the outer layer and the inner layer are each bonded to the intermediate layer with a peeling strength of 0.0490 to 3.4323 N/15 mm width as described above. Therefore, the intermediate layer is easily separated from the inner layer and from the outer layer when the laminated sheet is pierced with the suction means. The peeling strength between the outer layer and the intermediate layer and the peeling strength between the intermediate layer and the inner layer are each set in the range of 0.0490 to 3.4323 N/15 mm width for the following reason. If the peeling strength is lower than 0.0490 N/15 mm width, the outer layer, the intermediate layer and the inner layer of the laminated sheet are too easily separated from one another in handling the laminated sheet before the production of the bag, resulting in a poor operability. Where the unstretched film is provided in the inner surface of the outer layer, however, delamination of the laminated sheet of the bottom portion along the seam between the bottom portion and the body portion of the finished bag is prevented even if the peeling strength is low. This is because the unstretched film in the inner surface of the outer layer, the unstretched film of the intermediate layer and the unstretched film of the inner layer of the bottom portion are fusion-bonded together to the unstretched film of the inner layer of the body portion along the seam by the heat sealing. Where the unstretched film is not provided in the inner surface of the outer layer, a peeling strength of 0.3432 to 3.4323 N/15 mm width between the outer layer and the intermediate layer is required. If the peeling strength between the outer layer and the intermediate layer or between the intermediate layer and the inner layer is higher than 3.4323 N/15 mm width, the intermediate layer is less liable to be separated from the outer layer and from the inner layer when the bag is pierced with the suction means. The easy separation between the outer layer and the intermediate layer and between the intermediate layer and the inner layer occurring when the laminated sheet is pierced with the suction means permits the outer layer, the intermediate layer and the inner layer to be disconnected from one another at two stages. If the outer layer is torn by the piercing, the intermediate layer is disconnected from the outer layer thereby to be prevented from being torn, and the inner layer is disconnected from the intermediate layer thereby to be prevented from being torn. Even if the intermediate layer happens to be torn, the inner layer is prevented from being torn. Further, even if the inner layer happens to be torn with no tear in the intermediate layer, at least the inner layer or the intermediate layer is intimately fitted around the suction means which pierces into the bag, so that air is unlikely to flow into the bag. Therefore, if the material contained in the bag is reduced to a small quantity, the material remaining in the bag can almost completely be delivered out of the bag.
The bag according to the third inventive aspect is constructed such that the film structure of the outer layer and the film structure of the intermediate layer in the bag according to the second inventive aspect are interchanged with each other. More specifically, the outer layer is comprised of a laminated film including an unstretched polyolefin film and another unstretched film, e.g., an unstretched nylon film, and the intermediate layer includes at least one of a calendered film such as an aluminum film and an unstretched film. The other features of the construction of the bag is the same as those according to the second inventive aspect. In accordance with the third inventive aspect, the intermediate layer is easily separated from the outer layer and from the inner layer.
Therefore, the outer layer, the intermediate layer and the inner layer are disconnected from one another at two stages. If the intermediate layer is torn by the piercing with the suction means, the outer layer is disconnected from the intermediate layer thereby to be prevented from being torn, and the inner layer is disconnected from the intermediate layer thereby to be prevented from being torn. Even if the outer layer happens to be torn, the inner layer is prevented from being torn. Further, even if the inner layer happens to be torn with no tear in the outer layer, at least the inner layer or the outer layer is intimately fitted around the suction means which pierces into the bag, so that air is unlikely to flow into the bag. Therefore, if the material contained in the bag is reduced to a small quantity, the material remaining in the bag can almost completely be delivered out of the bag.
The bags for the liquid or powdery material according to the first to third inventive aspects may be of a so-called stand-pack type (self-supporting type) which is to be set upside down in the container as described above, of a pillow type, of a three side seal type, of a four side seal type, of a tetra-pack type, or of a gusset type which has four faces with longitudinally opposite side edges thereof closed by heat sealing and is inserted in the container with longitudinally opposite portions thereof folded toward each other to centrally gather the liquid or powdery material contained therein. In the bags of any of the aforesaid types, the penetrable portion to be pierced with the suction means projecting from the liquid or powder dispenser is formed of the double-layer laminated sheet having the outer layer and the inner layer or of the triple-layer laminated sheet having the outer layer, the intermediate layer and the inner layer. The present invention is also applicable to a bag for containing an ink for a printer or the like. In this case, the hollow needle suction means is employed instead of the tubular suction means for piercing into the ink bag set in the printer or the like. With one end of the needle suction means inserted into the ink bag, the ink is delivered out of the ink bag from the other end of the needle suction means. It is noted that the peeling strength as set forth in the first to third inventive aspects is determined in conformity with the test method for heat-seal peeling strength specified in JIS K 6854.
With the construction according to the first inventive aspect, the outer layer and the inner layer are bonded to each other with a peeling strength of 0.0490 to 3.4323 N/15 mm width, so that the inner layer is easily separated from the outer layer when the laminated sheet is pierced with the tubular or needle suction means. The easy separation between the outer layer and the inner layer occurring when the laminated sheet is pierced with the suction means permits the inner layer to be disconnected from the outer layer thereby to prevent the inner layer from being torn even if at least one of the calendered film (aluminum foil) and the stretched film is torn by the piercing. Therefore, at least the inner layer is intimately fitted around the suction means which pierces into the bag, so that air is unlikely to flow into the bag. Even if the material contained in the bag is reduced to a small quantity, the material remaining in the bag can almost completely be delivered out of the bag. With the constructions according to the second and third inventive aspects, the outer layer and the inner layer are each bonded to the intermediate layer with a peeling strength of 0.0490 to 3.4323 N/15 mm width, so that the intermediate layer is easily separated from the outer layer and from the inner layer when the laminated sheet is pierced with the suction means. The easy separation between the outer layer and the intermediate layer and between the intermediate layer and the inner layer occurring when the laminated sheet is pierced with the suction means permits the outer layer, the intermediate layer and the inner layer to be disconnected from one another at two stages. Even if one of the outer layer and the intermediate layer is torn by the piercing with the suction means, the other layer is disconnected from the one layer thus torn thereby to be prevented from being torn, and the inner layer is disconnected from the intermediate layer thereby to be prevented from being torn. Even if the outer layer and the intermediate layer happen to be torn, the inner layer is prevented from being torn. Further, even if the inner layer happens to be torn with no tear in the intermediate layer or the outer layer, at least one of the inner layer, the intermediate layer and the outer layer is intimately fitted around the suction means which pierces into the bag, so that air is unlikely to flow into the bag. Therefore, if the material contained in the bag is reduced to a small quantity, the material remaining in the bag can almost completely be delivered out of the bag.